Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by an expanding glutamine repeat in a gene termed IT15 or huntingtin.sup.1. Although this gene is widely expressed.sup.2-9 and is required for normal development.sup.10-12, the pathology of HD is restricted to the brain, for reasons that remain poorly understood. The huntingtin gene product is expressed at similar levels in patients and controls, and the genetics of the disorder.sup.13,14 suggest that the expansion of the polyglutamine repeat induces a toxic gain of function, perhaps through interactions with other cellular proteins.sup.15-18.
There is a need in the art for identification of the cellular components which are involved with huntingtin so that the disease can be better understood, diagnosed, and treated.